1. Field of the Invention
The present invention relates to a high-frequency module for use in an information communication apparatus such as a cellular phone, for example.
2. Description of the Related Art
In the related art, various high-frequency modules for transmitting and receiving a plurality of high-frequency signals using different frequency bands with one antenna have been devised. Such a high-frequency module in general includes a switch module which performs switching between high-frequency signals, switching between transmission and reception of each high-frequency signal, and the like, a power amplifier module on a receiving side, and a SAW (Surface Acoustic Wave) filter module on a transmitting side. The high-frequency module is formed as an integrated module in which each module is finally packaged.
For example, the high-frequency module disclosed in Japanese Unexamined Patent Application Publication No. 2006-319512 is composed of a module substrate formed by a laminate having a predetermined electrode pattern, and a SAW filter and the like which are mounted on a principal surface of the module substrate.
Further, the switch module includes a high-frequency integrated circuit (hereinafter, referred to as high-frequency IC: Integrated Circuit), and the high-frequency IC in general often includes a PLL (Phase Locked Loop) circuit (e.g., see Japanese Unexamined Patent Application Publication No. 2006-33108). The PLL circuit often uses a charge pump circuit as a power supply circuit.
However, when the high-frequency IC, which is disclosed in Japanese Unexamined Patent Application Publication No. 2006-33108 and includes the charge pump circuit, is configured as an integrated high-frequency module as disclosed in Japanese Unexamined Patent Application Publication No. 2006-319512, the high-frequency IC may malfunction or may not operate as a result of the modularization.
Further, it is known that when modularized as disclosed in Japanese Unexamined Patent Application Publication No. 2006-319512, a high-frequency IC (Integrated Circuit) which is to be mounted and has a connection terminal to be connected to an electrode of a substrate is mounted on the substrate and subjected to resin molding. In this case, even when a combination of characteristics is adjusted prior to the modularization, the characteristics of the high-frequency IC change due to factors such as generation of static electricity in a modularizing step. As a result, the characteristics of the high-frequency module are different from design standards.
Further, as one of the factors for the characteristic change of the high-frequency IC, it is known that a power supply circuit section of the high-frequency IC breaks down and cannot apply a necessary voltage to a predetermined functional circuit. For example, in a high-frequency IC which performs a switching operation of switching a connection between a plurality of ports, when a power supply circuit section thereof breaks down, unintended ports may be connected to each other or the switching operation itself may not be performed.
In this case, the characteristics of the high-frequency IC cannot be individually confirmed after the modularization. Thus, it is difficult to recognize whether the factor for the characteristics of the high-frequency module being different from design standards is attributed to characteristic change of the high-frequency IC or a defect such as breakage of a signal path of a module substrate section. Thus, when a defect occurs in the characteristics of the high-frequency module, a lot of time and effort must be spent to identify the factor that caused the defect and to improve the characteristics of the high-frequency module.